Monday, August 25, 2008

Field trip to Schluckebier and Gasser Sand Prairies

Yesterday Ted Cochrane (in the middle in the above photo) from the U.W. Herbarium led a very informative field trip to two sand prairies in Sauk County, Schluckebier and Gasser. These prairies are owned by the Nature Conservancy but managed for them by the Prairie Enthusiasts.

Sand prairies have an interesting suite of plant species, some also common to other dry prairies and some unique to sand. Schluckebier has the more "normal" prairie flora than Gasser, with lots of rough blazing star in bloom, among other things.

At the nearby Gasser Sand Prairie we saw two species that are less common. The one to the left is fame flower (Phemeranthus rugospermus), a member of the purslane family (Portulaceae). This rare species is usually found on the driest sandy soil. Its tiny blossoms only open in the afternoon for about 3 hours and then fade. Our timing was great, as there were quite a few flowers showing during our late afternoon visit. In Wisconsin it is found almost exclusively in the western and southern parts of the state, its distribution almost tracing the boundaries of the Driftless Area. This is a State-listed species (Special concern).

The other species is poppy mallow (Callirhoe triangulata), another Special Concern plant. This rare, showy, sand prairie species is almost solely confined to the Upper Midwest. In Wisconsin it is mostly confined to the dry sandy valleys of the Wisconsin and Mississippi Rivers. (The sand from Gasser Prairie derives from a high water phase of the Wisconsin River during the retreat of the last glacial period.) I have only seen it during field trips to southwest Wisconsin and northwest Illinois. It is always a treat to see it.

According to various gardening web sites, both of these species can be raised in open flower beds, and seeds can be purchased. Because of their rarity, seeds should never be collected from nature.